Q.What Can I Use To Treat Rust On A Mugho Pine Shrub? (for Organic Gardening)
in the spring I used (garden safe) Fungicide 3. It did promote new growth but the branches are covered in rusted needles. Will those branches regrow with treatment?
Certified GKH Gardening Expert
Fungicides do best at preventing fungal diseases, not curing it. Your best bet is to prevent any further disease by making sure your plant has good air circulation, plenty of sun, no overhead watering, and cleaning up any needles that drop.
You can prune out the affected branches if it's not extensive.
https://www.gardeningknowhow.com/ornamental/trees/pine/mugo-pine-information.htm